Blood oxygenator

Abstract

The present disclosure describes a blood oxygenator that includes a checkerboard layout of fluid (e.g., blood) and gas (e.g., oxygen) channels. When viewed as a cross-section through each of the channels of the oxygenator, the checkerboard configuration includes alternating gas and fluid channels in both the x-axis (e.g., in-plane) and in the y-axis (e.g., out-of-plane) directions. The oxygenator described herein reduces manufacturing complexity by using first, second, and third polymer layers that include asymmetrical channel designs. The channel designs include “open” gas channels, which are exposed to the ambient atmosphere. The oxygenator is placed within a pressure vessel to drive gas into each of the open gas channels, which in some implementations, negates the need for a gas manifold.

What is claimed: 
     
       1. An oxygenator comprising:
 a first polymer layer comprising a first plurality of gas channels and a first plurality of fluid channels; 
 a second polymer layer comprising a second plurality of gas channels and a second plurality of fluid channels, each of the second plurality of gas channels overlapping one of the first plurality of fluid channels and each of the second plurality of fluid channels overlapping one of the first plurality of gas channels; 
 a third polymer layer comprising a third plurality of gas channels and a third plurality of fluid channels, each of the third plurality of gas channels overlapping one of the second plurality of fluid channels and each of the third plurality of fluid channels overlapping one of the second plurality of gas channels; and 
 a plurality of gas vias defined in the second polymer layer, each of the plurality of gas vias coupling one of the first plurality of gas channels to one of the third plurality of gas channels. 
 
     
     
       2. The oxygenator of  claim 1 , further comprising a second plurality of gas vias defined in the first polymer layer and a third plurality of gas vias defined in the third polymer layer. 
     
     
       3. The oxygenator of  claim 1 , wherein the first plurality of gas channels and the third plurality of gas channels define a first gas flow network and the second plurality of gas channels defines a second gas flow network. 
     
     
       4. The oxygenator of  claim 1 , wherein each of the second plurality of fluid channels are substantially vertically aligned with one of the first plurality of gas channels, each of the third plurality of gas channels are substantially vertically aligned with one of the second plurality of fluid channels, and each of the third plurality of fluid channels are substantially vertically aligned with one of the second plurality of gas channels. 
     
     
       5. The oxygenator of  claim 1 , wherein the first plurality of gas channels and the first plurality of fluid channels are arranged in an alternation pattern, the second plurality of gas channels and the second plurality of fluid channels are arranged in the alternation pattern, and the third plurality of gas channels and the third plurality of fluid channels are arranged in the alternation pattern. 
     
     
       6. The oxygenator of  claim 5 , wherein the alternation pattern comprises a strict alternation of gas channels and fluid channels. 
     
     
       7. The oxygenator of  claim 1 , further comprising a pressure vessel housing the first, second, and third polymer layers. 
     
     
       8. The oxygenator of  claim 7 , wherein an inlet to the first, second, and third plurality of gas channels is open to an ambient environment within the pressure vessel. 
     
     
       9. The oxygenator of  claim 1 , wherein the first plurality of gas channels and the first plurality of fluid channels are configured in an asymmetrical channel layout, and the second plurality of gas channels and the second plurality of fluid channels are configured in the asymmetrical channel layout. 
     
     
       10. The oxygenator of  claim 1 , wherein the second and third polymer layers are each a copy of the first polymer layer. 
     
     
       11. The oxygenator of  claim 10 , wherein the second polymer layer is rotated 180 degrees with respect to the first and third polymer layers. 
     
     
       12. The oxygenator of  claim 1 , wherein each of the channels of the first, second, and third plurality of gas channels comprise a dead end. 
     
     
       13. The oxygenator of  claim 1 , wherein each of the plurality of gas vias is positioned between two of the plurality of fluid channels of the second polymer layer. 
     
     
       14. The oxygenator of  claim 1 , wherein each of the plurality of gas vias is aligned with a longitudinal axis of one of the plurality of fluid channels in the second polymer layer. 
     
     
       15. The oxygenator of  claim 1 , wherein a depth of the first, second, and third plurality of fluid channels is between about 40 μm and about 250 μm. 
     
     
       16. The oxygenator of  claim 1 , wherein the first, second, and third polymer layers each comprise Poly(DiMethylSiloxane). 
     
     
       17. The oxygenator of  claim 1 , wherein the first, second, and third polymer layers each have a gas permeance greater than about 1×10 −6  mL/s/cm 2 /cm Hg. 
     
     
       18. A method of oxygenating blood, the method comprising:
 providing an oxygenator according to  claim 1 ; 
 introducing oxygen into pressure vessel housing the oxygenator; 
 introducing at least partially deoxygenated blood into the oxygenator; and 
 receiving at least partially oxygenated blood from the oxygenator. 
 
     
     
       19. The method of  claim 18 , further comprising pressurizing the pressure vessel with the introduced oxygen to a pressure of between about 1.0 atms and about 2.5 atms. 
     
     
       20. The method of  claim 18 , further comprising pressurizing the pressure vessel with the introduced oxygen to a pressure of between about 2.0 atms and about 3.0 atms. 
     
     
       21. The method of  claim 18 , further comprising introducing the at least partially deoxygenated blood into the oxygenator at a rate of between about 500 mL/min and about 7 L/min.